The present invention relates generally to an electrical connector and, more particularly, to a novel unitary connector body having a conductive shell, and a method of making the same.
Typically, an electrical connector comprises an insulator containing a plurality of contacts, and a separate metal shell surrounding the insulator. The shell provides grounding and RF shielding for the connector. Since the shell and insulator are separate parts, it will be appreciated that the cost of assembling the connector makes the connector more expensive than one-piece plastic connectors without metal shells. However, the latter connectors are unsuitable when grounding and shielding are required. Furthermore, sometimes voids occur between the insulator and the shell in the two-piece connector in which moisture may become entrapped thereby impairing the operating characteristics of the connector.
Accordingly, it is one object of the present invention to provide a unitary, one-piece electrical connector body having a conductive shell portion for providing grounding and/or RF shielding.
As will be seen as this description proceeds, the connector body of the present invention is made by the use of a double shot molding process, which broadly speaking is not new. Double shot molding, sometimes also referred to as dual color molding, has been used previously in the connector art as well as in the manufacture of buttons for keyboards, for example. With respect to the pertinent connector prior art, reference is made to British Pat. No. 968,707 which discloses a unitary connector insulator having a hard contact mounting portion with a relatively soft resilient grommet portion integral therewith. The mold assembly used to produce the insulator initially contains a "dummy" plate and a first mold cavity plate. A first shot of insulating material is made into the first mold cavity plate to form the contact mounting portion of the insulator. The dummy plate is then removed and replaced with a second mold cavity plate into which a second shot of insulating material is made to form the grommet. Thus, the mold assembly must be disassembled in order to form the unitary insulator body.
It is a further object of the present invention to provide a novel double shot molding process for forming the unitary electrical connector body of the invention, which does not require disassembly of a mold during the two steps of injecting molding compound into the mold.
An electrical connector made by the use of a dual color molding process is disclosed in U.S. Pat. No. 3,998,512 to Anhalt et al. In FIG. 5 of the Anhalt patent, there is disclosed a watch connector comprising a plurality of conductive silicone rubber strips integral with a non-conductive silicone rubber backing sheet. The conductive strips from the contacts of the connector. The connector does not incorporate a conductive shell surrounding an insulator containing contacts as does the connector of the present invention.